"Two roads diverged in the wood, and I - I took the one less traveled by, and that has made all the difference." – Robert Frost

" The road we have long been traveling is deceptively easy, a smooth superhighway on which we progress with great speed, but at its end lies disaster. The other fork of the road - the one less traveled by - offers our last, our only chance to reach a destination that assures the preservation of the earth."
– Rachel Carson

Since their origin in the 1950s, PFAS (per- or poly-fluoroalkyl substances) chemicals have been used in products from cooking spray to firefighting foam to pizza boxes. Originally invented to help repel water, heat, and grease, PFAS chemicals are commonplace in nearly everything we encounter in our daily lives. Once touted as "safe" by manufacturers, PFAS substances have been dubbed "Forever Chemicals" by the United States Environmental Protection Agency (EPA) – chemicals that do not break down easily or spontaneously. This results in the accumulation of these toxins in the air, soil, water, and food supply. PFAS and PFAS-related compounds have been linked to numerous health problems, including those listed below:

• Multiple types of cancer
• Diabetes, thyroid disease, and other endocrine disorders
• Miscarriages, preeclampsia, and birth defects
• Asthma and respiratory disorders
• Heart disease and high cholesterol
• Liver disease and gastrointestinal disorders

Previous articles in this series have addressed health and safety concerns associated with PFAS contamination. We have discussed the history of PFAS, the health effects on the current and future generations related to its use, and the need to implement responsible product sourcing to prevent further contamination of our air, soil, water, and food supply. Awareness of the impacts and reducing new sources of PFAS pollution are important parts of the overall solution. However, unless we take measures to remove the existing contamination now, attaining a world that is “Forever Free” from PFAS will not be possible. Removing PFAS from the environment is the only way to remove these toxins from our food, our animals, and ourselves.

Scientists measure the breakdown of chemicals in plants, animals, people, and the environment in terms of "half-lives." One half-life is the amount of time needed to reduce the level of a given chemical or substance by one-half. To be statistically undetectable, five half-lives must pass, either by breakdown or elimination. The half-life of PFAS in animals and people takes up to eight years, provided there is no new exposure. Thus, even after removing PFAS from our environment, it will take another 40 years for these substances to be eliminated from all living things.

PFAS has one of the strongest known chemical bonds. This characteristic prevents natural decay that would result from oxidation or ultra-violent light and renders standard toxin removal methods ineffective. As one comparison, petroleum byproducts will break down on their own and have a half-life of 25 to 50 years. Bacteria will degrade PFAS eventually, but the process is exceedingly slow. Multiple studies have shown that just one half-life will take over 1,000 years! This means that even if all PFAS manufacturing stopped today, bacterial degradation alone would require more than 5,000 years to remove PFAS-related chemicals from all plants, animals, people, and environments.

Current approaches to the large-scale removal of toxins and pollutants from habitats are to bury, store, or burn the offending materials. Activated carbon adsorption, ion exchange resins, and high-pressure membrane filtration are used to collect and concentrate PFAS contamination from wastewater and drinking water. Burying and storage seek to separate toxic materials from the environment and living things until the material breaks down naturally. For most chemical compounds, this requires only a few decades, while radioactive materials will take centuries to decay.  PFAS chemicals take millennia – longer than containers for storage and burying will last. This results in the seepage of PFAS into surrounding areas, further contaminating the soil and water. Burning of PFAS compounds – even at incineration temperatures – is not effective. All that burning does is aerosolize the toxins without destroying them, which is why this practice now prohibited by the EPA. Unfortunately, there is no global ban on PFAS burning.  Super high-temperature incineration has been tried most often but merely reorganizes the PFAS compounds, trading one durable toxin for another. In addition, this procedure is very expensive to scale to industrial clean-up levels, contributes to greenhouse gases, and conflicts with multiple EPA and WHO mandates. Burying, burning, and storing are not solutions to PFAS pollution.

Scientists and engineers have spent years inventing technologies to accelerate the degradation of "forever chemicals." Emerging technologies have demonstrated that the half-life for PFAS chemicals can be shortened to hours and even minutes. While many of these technologies work well in the controlled setting of a laboratory using small models, effectiveness against PFAS compounds is lost when the same technologies are tested for larger remediations. In Part 2 of this article, we will discuss a cost-effective, scalable technology that remediates PFAS without leeching, aerosolization, or generating new toxic byproducts.

Regulation, avoidance, substitution, and remediation are but four steps in a journey along the road less traveled. That road holds the promise of leading us to the successful removal of PFAS chemicals from our bodies and our habitats. Indeed, this would be the road to a healthier, “Forever Free” world.